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Project CP/59 - “Instruments and institutions to develop local food systems” 1.3.3.2. Life cycle analysis (LCA) or life cycle energy consumption In LCA, all energy inputs needed during the entire life cycle of a product are taken into account as completely as possible. In this way, one obtains a general image of the energy consumption necessary to produce a given food product and to bring it ready-toeat on the dish of the consumer. For example, for agricultural products Carlsson-Kanyama et al. (2003) include: the agricultural production containing agricultural inputs, the drying of the crops, the processing, stocking and transportation to the retailer, as well as the stocking and the processing in the households. Packaging materials, waste treatment, capital goods such as machines and the transport from the retailer to the consumer are not taken into account. Life cycle energy inputs of food are calculated per kg food that is ready to eat. These are then used in order to calculate the energy inputs per portion, which can then be added together to meals (Carlsson-Kanyama et al., 2003). This method provides a very complete image of the energy needed in the entire cycle of a food product. Studies using these methods are therefore often the foundation of strategies for energy reduction in the food chain (Gerbens-Leenes et al., 2003). Also, based on the LCA, various products can be compared in an objective way. Energy inputs are not always exactly definable. For instance because the quantity of energy consumed has to be divided between various (side) products, or because the transport is a combination of collecting and delivery of various products at various places (personal communication Dirk Hebben). This is certainly the case for smaller, less specialized businesses. 1.3.3.3. Energy ratio The energy ratio is the relation between the energy output of the end product and the sum of the different energy inputs (Jones, 2001). The energy output is the energy contents of a food product (in calories). The energy inputs contain all energy consumed in the production, processing, packaging and distribution of the product, in short the LCA (Jones, 2001). In this way, one can check whether more energy has been used during production, processing, transportation, preparation,… of the product than the energetic value it supplies when being consumed. 1.3.3.4. Life cycle greenhouse gas emission The principle when calculating the ‘emission of greenhouse gases during the life cycle’ is pretty much analogous to the principle used for calculating the ‘energy consumption during the life cycle’ (LCA): the emissions of the different greenhouse gases in the different stages of the entire life cycle of a product are accounted for as meticulously as possible. The emissions of the different greenhouse gases can then be summed by making use of the ‘Global Warming Potentials’ of these gases and this is then expressed in grammes of CO2-equivalent (data from the Intergovernmental Panel on Climate Change (IPCC), 2001 of www.eia.doe.gov/oiaf/1605/gwp.html). The most important emission stages can then be identified for the different food products. SPSD II - Part I - Sustainable production and consumption patterns - Agro-Food 21
Project CP/59 - “Instruments and institutions to develop local food systems” In general, the environmental problems caused by the intensive energy consumption remain very important. This is mainly because of the emission of greenhouse gases from burning fossil fuels, which is at present the most widely used source of energy in the world. At the economic level, there is also the problem of exhaustion of these fuels in time, even though there are still large oil reserves known right now (Pervanchon et al., 2002). The emission of the most important greenhouse gases, like CO2, CH4, N2O and halogenised gases, are strongly related to food production and consumption, mainly because of the many human induced activities during the life cycle of these products. Not only these gases, but also CO, NOx, benzene, photochemical smog, … cause greenhouse effects (Jones, 2001). N2O is mainly liberated in the production of nitrogen fertilisers and cattle breeding produces large quantities of methane (CH4) (Carlsson- Kanyama, 1998). Then again, NOx is involved in causing more acidity in the ecosystem, eutrophication and the origination of ozone in the troposphere. The burning of fossil fuels causes mainly emission of CO2 (Pervanchon et al., 2002). An efficient use of energy in production, processing, transport, conservation etc. of food is therefore one of the conditions for more sustainable food systems, and it will also be crucial to not exhaust the fossile sources of energy and to stabilise the concentrations of CO2 and other detrimental gases in the atmosphere (Carlsson-Kanyama et al., 2003). A comparison between the LCA and the life cycle emission shows that important stages are being underestimated if only the use of energy is taken into account. This could for instance lead to adopting suboptimal policy measures. Therefore, it is important that the life cycle emissions are also considered (Carlsson-Kanyama, 1998). Here also, there is the problem of the exact quantification of a number of emissions, such as the definition of energy consumptions for the LCA. 1.3.3.5. Ecological footprint (EFP) According to Wackernagel and Rees (1996), the formal definition of the ecological footprint (EFP) is as follows: the EFP of a specific population or economy measures the claim or the ecological impact of humans upon nature. It is a measure for the quantity of land (and water) that is needed to maintain a population of any size. The EFP is therefore measured as the quantity of biologically productive land (and water) needed to continuously maintain a population’s consumption level on a given moment in time (Anderson and Lindroth, 2001; www.gdrc.org/uem/footprints/what-is-ef.html). The EFP is one of the few instruments that do not express the value “nature” in monetary terms. As the total value of ‘the utilities/services the ecosystem offers us’ can be seen as endlessly large, because life without it would be impossible (Borgström Hansson and Wackernagel, 1999). The impact of the human being on a global scale comes forth from three processes: (1) an increase of the CO2 concentration in the atmosphere because of the consumption of fossil fuels, (2) an increase of the fixation of nitrogen by the production of industrial fertilisers and (3) a change in the use and coverage of land. SPSD II - Part I - Sustainable production and consumption patterns - Agro-Food 22
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